A lithographic apparatus is a machine that applies a desired pattern onto a target portion of a substrate. Lithographic apparatus can be used, for example, in the manufacture of integrated circuits (ICs). In that circumstance, a patterning device, such as a mask, may be used to generate a circuit pattern corresponding to an individual layer of the IC, and this pattern can be imaged onto target portions, including dies or die parts, on a substrate (e.g. a silicon wafer) that has a layer of radiation-sensitive material (resist). In general, a single substrate contains a network of target portions that are successively exposed. Known lithographic apparatus include so-called steppers, in which each target portion is irradiated by exposing an entire pattern onto the target portion in one go, and so-called scanners, in which each target portion is irradiated by scanning the pattern through the projection beam in a given direction (the “scanning”-direction) while synchronously scanning the substrate parallel or anti-parallel to this direction.
From the U.S. Pat. No. 6,447,964 patent, a charged particle beam microlithography method is known, in which regions of the substrate where entire dies are formed are exposed first, followed by regions—especially peripheral regions—with only portions of dies. Several exposure sequences are described for exposing the substrate, for example, a spiral sequence in which exposure of functional-device chips is performed in a spiral sequence, progressing inward, after which fragmentary chips, which typically surround the functional-device chips, are exposed.